Xylella: What Is It? What Problems Is It Causing? How Can We Solve Them?

First discovered in Italy, Xylella fastidiosa is a bacterium which causes disease in a variety of commercial plants, including citrus plants and several species of broadleaf trees widely grown in the UK. While Xylella isn’t currently present in our country, the UK is still on high alert given the significance of the threat.

In this article we’ll be taking an in-depth look at Xyella, detailing what can be done to combat some of the key problems we face as a result of it.

What is it?

Classed as one of the most harmful plant pathogenic bacteria in the world, Xylella lives in the water conducting vessels (xylem) of plants, moving both upstream and downstream. By doing this, Xylella restricts the movement of water and nutrients through the plant, starving it.

In nature, the bacteria are exclusively transmitted by insects from the Cicadellidae and Ceropidae families, such as leafhoppers and spittlebugs, which feed on plants’ xylem fluid. Although these sorts of insects usually only fly short distances of around 100 metres, the wind can carry them much further than that making infection more widespread.

What problems is it causing?

Discovered in Italy in 2013 when a large group of olive trees in Lecce became diseased, Xylella has since spread throughout Corsica, France and other areas of mainland Europe throughout the following years thanks to a plethora of insect vectors. Given the sheer prevalence of such insects in certain countries, Xylella can spread through woodland areas at an alarming rate, to devastating effect. In the wild this sort of widespread infection tends to occur during warmer seasons, when insect vector populations are at their highest.

Infection by Xylella can result in a number of symptoms, such as leaf scorch, stunted growth, reduction in fruit quality and size and dieback. However, many infected plants demonstrate no symptoms. This can be particularly dangerous, as these plants can provide a reservoir for reinfection of other plants. This cycle can make Xylella extremely difficult to detect and control

What can we do about it?

Given how difficult it is to identify different instances of Xylella, infection control isn’t always easy, however, it’s certainly very important.

Currently, Xylella is subject to EU emergency measures. The control strategy here primarily aims to keep the bacterium out of its member states with very rigorous inspections. In the UK, landings of Xylella host species, such as elm and oak trees, must be made aware to plant health authorities as quickly as possible. This way, thorough inspections can be made before they make their way into the mainland.

Other regulations include restricted movements of specified host plants from the infected region of Apulia in southern Italy, and from third party countries outside the EU. This further reduces the risk Xylella spreading unchecked.

Based near Weybridge, Creepers are a specialist wholesale nursery for the luxury garden market. We offer a wide range of services, including the sourcing and growing of topiary specimens, garden design and installation services. With over 20 years of experience, we’ve built strong relationships with the finest growers in the UK, so you can expect only the highest quality of plants. For more information about Creepers, don’t hesitate to get in touch.